Document feeder control circuit

ABSTRACT

A document feeder transfers original documents placed in a stack one at a time in succession into a copying position on an exposure platen of a copy machine. The control circuit for the feeder includes means for initiating the feeding of an original document from a stack of original documents in the tray of the document feeder into and along a transport path. The control circuit additionally enables the document feeder to expel an original document from the exposure platen of a copy machine after a desired number of copies have been made. The control circuit further includes means to prevent the feeding of further original documents into and along the transport path until the desired number of copies of a previously fed original document are completed. The control circuit further controls the initiation of the copying process of the copy machine. Additionally, means are provided to detect the jamming of an original document during its expulsion from the exposure platen of the copy machine.

United States Patent 1 Margulis et al.

[111 3,747,918 July 24, 1973 DOCUMENT FEEDER CONTROL CIRCUIT [75]Inventors: Harry Margulis, Hofmann Estates;

Roy 1). Korff, Elk Grove Village, both of 111.

[73] Assignee: Addressograph-Multigraph Corporation, Mount Prospect,Ill.

122 Filed: was;155

[52] US. Cl 271/4, 27l/47, 271/ [51] Int. Cl. B6511 5/02, Bh 7/20 [58]Field of Search 271/4, 10, 47, 57,

[56] References Cited Primary Examiner-Evon C. Blunk AssistantExaminer-Bruce H. Stoner, Jr. Attorney-Richard D. Mason et a1.

[57] ABSTRACT A document feeder transfers original documents placed in astack one at a time in succession into a copying position on an exposureplaten of a copy machine. The control circuit for the feeder includesmeans for initiating the feeding of an original document from a stack oforiginal documents in the tray of the document feeder into and along atransport path. The control circuit additionally enables the documentfeeder to expel an original document from the exposure platen of a copymachine after a desired number of copies have been made. The controlcircuit further includes means to prevent the feeding of furtheroriginal documents into and along the transport path until the desirednumber of copies of a previously fed original document are completed.The control circuit further controls the initiation of the copyingprocess of the copy machine. Ad- UNITED STATES PATENTS ditionally, meansare provided to detect the jamming of 3,567,214 3/1971 Crandell et a1.271/10 an Original document during its expulsion from the 3,408,14010/1968 l-lemphill posure platen of the copy machine. 3,153,962 10/1964Mercer et al. 3,626,956 12/1971 Sander 271/57 3 Claims, 9 DrawingFigures 90 72 2 16 J t, 42 -2 ,18 38311 3438 m 54 o A .94 J05 22 FB 12 QQ PAIENIED JUL24I975 3 747, 918

SHEET 3 BF 4 PATENTE D JUL 2 41975 SHEET 8 [IF 4 mlawsxu MUS .23". 5125225 uziuei K8 DOCUMENT FEEDER CONTROL CIRCUIT BACKGROUND OF THEINVENTION This invention relates generally to a control circuit for adocum ent feeder used to transfer documents from a stackcontained in atray one at a time in succession into a copying position on an exposureplaten of a copy machine. The invention control circuit integrates theoperation of the document feeder with a copying machine so that anydesired number of copies of an original document may be automaticallyproduced. The circuit controls the removal of an original document fromthe exposure platen after the desired number of copies have been madeand further controls the transfer of a next original document intoposition on the exposure platen for copying.

SUMMARY OF THE INVENTION An object of the present invention is toprovide a new and improved control circuit for a document feeder.

Another object of the present invention is to provide a new and improvedcircuit of the character described which is operable to control thefeeding of original documents one-by-one into a copying position on anexposure platen of a copy machine so that any selected number of copiesmay be automatically reproduced.

A further object of the present invention is to provide a new andimproved control circuit of the character described that is operable toinitiate the copying process of a copy machine and is further operableto monitor the transfer of an original document out of the transportpath of a document feeder.

Briefly, the present invention is especially adapted to control thetransfer of original documents, from a document feeder such as shown inthe copending US. Pat. application ,Ser. No. 201,043, filedcontemporaneously, which application is assigned to the same assignee asthe present application, one at a time in succession into a copyingposition on an exposure platen of a copy machine, such as shown in thecopending US. Pat. application Ser. No. 889,594, filed Dec. 31, 1969,now Pat. No. 3,663,102 which application is assigned to the sameassignee as the present application. The control circuit provides meansfor initiating the feeding of an original document into and along thedocument transport path of a document feeder. The control circuitfurther includes means to cause the correct positioning of an originaldocument of the exposure platen of a copy machine and means forinitiating the copy process of a copy machine. The control circuit ofthe present invention further includes means causing an originaldocument to be expelled from the transport path and for monitoring theexpulsion thereof to detect any possible jam of tht original document.Finally, the control circuit includes means for discontinuing theoperation of a document feeder and of a copy machine when the supply oforiginal documents is exhausted.

DESCRIPTION OF THE DRAWINGS For a better understanding of the inventionand its organization and construction, reference should be had to thefollowing detailed description taken in conjunction with theaccompanying drawings, in which:

FIG. 1 is a top plan view of a preferred embodiment of a document feederconstructed in accordance with the features of the present invention;

FIG. 2 is a bottom view of the document feeder of FIG. 1;

FIG. 3 is a longitudinal vertical sectional view, taken substantiallyalong line 3--3 of FIG. 1;

FIG. 4 is an enlarged fragmentary sectional view similar to FIG. 3.showing only one end portion of an endless belt with a document stopgate in its stopping or closed position;

FIG. 5 is a sectional view similar to FIG. 4 but showing the documentstop gate in an open position;

FIG. 6 is a perspective view of a preferred embodiment of an endlessbelt constructed in accordance with the features of the presentinvention;

FIG. 7 is a perspective view of the endless belt of FIG. 6 illustratedas formed in an endless belt loop;

FIG. 8 is a fragmentary cross-sectional view of a portion of the endlessbelt of FIGS. 6 and 7 illustrating a parallel, longitudinal ridge on anouter surface of the endless belt; and

FIG. 9 illustrates in schematic diagram form a preferred embodiment of acircuit for controlling the operation of document feeder.

DETAILED DESCRIPTION General Referring now more in detail to thedrawings, especially FIGS. l-5, therein is illustrated a document feederreferred to generally in FIGS. 1 and 2 by a reference numeral 10. Thedocument feeder 10 is adapted to be mounted on top of a copy machine 12(FIG. 3) which has an exposure platen 14 on which documents to be copiedare positioned. The aforementioned copending US. Pat. application Ser.No. 889,594 illustrates a copy machine which is readily integrated withthe document feeder.

As more fully described in this patent application, the copy machine 12includes xenon light sources 16 (FIG. 3) beneath a glass platen 14 whichis supported in a rectangular opening and is flush with an upper endwall of a rectangular support structure 18 of the copy machine. Thedocument feeder 10 is adapted to be positioned directly on top of theexposure platen 14, as shown, and operates in coordinated asoociationwith the copy machine 12.

Endless Belt The document feeder 10 includes an endless feed belt 20(FIGS. 6, 7, and 8) formed of a thin, flexible, sheet material, such asMylar. This material is tough, strong, and opaque so that light will bereflected therefrom as the endless run of the belt slips easily over theupper surface of the platen 14 on the copy machine 12. The belt 20 (FIG.7) is formed into an endless belt loop and is fabricated by cutting onan angular bevel at opposite ends (FIG. 6) and beveling the edge thereofas indicated by the roughened edges 21 of the belt material. Theseportions are feathered to a sharp pointed edge so that they may bejoined together by cement or other suitable chemical fastening agents toform a uniform thickness endless belt 20. The joint between the edges isangular with respect to the direction of a plurality of longitudinalparallel ridges 28.

The belt 20 is trained over a pair of rollers 22 and 24 (FIG. 3) atopposite ends of the upper and lower belt runs. The lower belt run isadapted to move over and in parallel with the upper surface of theexposure platen 14 in associated copy machine 12. The roller 24 ispreferably composed of a high strength silicone rubber, such as GE 154silicone rubber, and has a high coefficient of friction with respect tothe Mylar surface of the belt 20 to rotate the belt 20 without slippage.

In order to frictionally engage and move a document 26 (FIGS. 4 and 5)into proper position on the platen 14 for copying by the copy machine12, the endless belt 20 is provided with a plurality of longitudinallyextending parallel ridges 28 (FIGS. 6, 7, and 8). The ridges 28 arepreferably composed of silicone rubber, are formed only on the outersurface of the endless belt, and are of a transverse cross-section,substantially comprising a chordal segment of a cylinder having a basewidth W (FIG. 8) which is considerably greater than a maximum height Hof the outer surface of the ridge 28 away from the outer surface of theadjacent belt 20. Since the ridges 28 are composed of silicone rubber,there is a higher coefficient of friction between the ridges 28 and theglass platen 14 than between the Mylar surface of the belt 20 and theglass platen 14. Thus, while the belt 20 easily slides across the platen14, the ridges 28 must be pulled across the platen 14 by the roller 24.The outer surfaces of the ridges 28 provide a frictional engagement withthe back side of the document 26 for movement of the document along theface of the platen 14 into a copying position (FIG. 4). The frictionalengagement is such that when the document 26 is in a copying position onthe exposure platen 14 of the copy machine 12 and is engaged by a stopsurface of a movable gate assembly 48 (FIG. 4), the outer surfaces ofthe ridges 28 will disengage from and slide over the base side of thedocument 26.

After the preselected number of copies have been made, the stop surfaceof the gate assembly 48 is removed (FIG. 5), and the endless belt 20 ismoved in a clockwise direction. The frictional engagement between thebelt ridges 28 and the back side of the original document 26 with thestop surface of the gate assembly 48 removed (FIG. 5) is sufficient tocause the document 26 to move to the left, as shown by the arrow A, fordischarge from the document feeder (FIG. 3).

Document Feeder The document feeder 10 (FIGS. 1 and 2) includes frontand back side members 30 and 32, which are structurally interconnectedby a plurality of transverse cross-members 34 (FIGS. 3, 4, and 5). Theendless belt (FIG. 3) is trained around the rolls 22 and 24 to runbetween and in a direction parallel of the sidewalls and 32 in aclockwise direction (FIG. 3), wherein an upper run of the belt 20 goesfrom left to right and a lower run of the belt 20 moves from right toleft along the upper surface of the exposure platen 14 of the copyapparatus 12.

Projecting forwardly of the front sidewall 30, the document feeder 10includes a control head 33 (FIG. I) which integrates the operation ofthe document feeder 10 with the copy machine 12. The control head 33includes means, generally indicated as 73 (FIG. 1), for programming adesired number of copies of an original document into an exposurecounter 113 (FIG. 9), a manual feed switch 111 (FIG. 1), and ajam lamp120 for indicating the presence of a jam of an original document at theexit of the document feeder 10.

An operator may place a stack of documents 26 (FIG. 1) to be copied in areceiving tray 36, and the documents will be picked up one at a time andfed in succession by means of the endless belt 20 into a copyingposition on the exposure platen 14 of the copy machine 12 (FIG. 4). Thenumber of copies of each document to be produced is programmed into thecontrol head 33 by the operator. The operation then becomes automatic sothat the operator may leave the facility and later return to find thatthe selected number of copies of all of the original documents 26 placedin the tray 36 have been reproduced by the copy apparatus 12.

The document feeder 10 further includes a miniature switch sensor 107(FIG. 3) referred to hereinafter as a feeder reset switch 107, locatedjust past a pair of rollers 68 and along the transport path and capableof being deflected by the passage thereby of an original document 26.The document feeder 10 also includes a photoelectric sensor (FIG. 3)located at the exit of the document feeder 10 for detecting the passageof an original document 26 thereby.

The lower run of the endless belt 20 moves the original documents 26into copying position from right to left in frictional engagement withthe back side thereof. In order to insure that adequate frictionalengagement is maintained between the belt and the document, a pluralityof backing members 38 (FIGS. 3-5) extend traversely between front andback sidewalls 30 and 32. The backing members 38 include lower channelportions having undersurfaces adapted to bear against the inside surfaceof the endless belt 20. The opposite ends of the backing members areprovided with vertical end flanges having slots therein for receivingmounting bolts 40 comprising sheet metal screws engaged in the front andrear plates 30 and 32. Thus, the backing members 38 may be adjustablypositioned in a vertical direction so that the undersurface thereofexerts a desired amount of downward pressure on the inside surface ofthe endless belt toward the exposure platen 14 of the copy apparatus. Toprevent sagging, the upper run of the endless belt 20 is supported by anupper backing plate 42 of generally channel-shaped configuration whichextends between front and back sides 30 and 32.

The belt rollers 22 and 24 are provided with outer sleeves 44 offrictional material, such as rubber, to provide good driving engagementbetween these rollers and the back side or inside surface of the endlessbelt 20. The roller 22 is supported on an idler axle 46 which issupported in suitable bearing means carried on the front and back sideplates 30 and 32.

The axle 46 also provides a support for a gate assembly 48 which ispivotally movable about the axle 46 between a stop or blocking position(FIG. 4) and an open position (FIG. 5) wherein the original document,after being copied, may be discharged as shown by the arrow A (FIGS. 3and 5). The gate assembly 48 includes a pair of end flanges 50 disposedat opposite ends of the roller 22 and journaled or pivotally mounted onthe axle 46. The end flanges are connected by a cross member 52 ofrelatively thick material.

A stop member 54 formed of relatively thin, flexible material, such assheet material or the like, is secured to the underside of the crossmember 52 and is supported in cantilever fashion thereon with a free endportion projecting outwardly of the cross member between the roller 22and the platen 14 (FIGS. 4 and 5). The stop member is of a consistencysimilar to a thin steel rule and is slightly flexible in nature yetrelatively strong. The outer edge of the free end portion of the stopmember forms a stopping surface adapted to engage the upper surface ofexposure platen 14 (FIG. 4). A strip of resilient material 56 is affixedto the stop member to provide a continuation of a stopping surface toengage the end of the original document 26 (FIG. 4), should its end tendto curl upwardly away from the upper surface of an exposure plate. Theresilient strip 56 serves a dual function in providing an extension ofthe stop surface of the outer end of the member 54 and in contacting thebelt to provide cleaning action therefor by removing articles or thelike which may cling to the outer surface thereof.

The gate assembly 48 is pivotally movable about the axle 46 between twospaced positions. The stop or blocking position is shown in FIG. 4wherein the end of the original document 26 is engaged and held in adesired position for copying on the exposure platen 14. When the copyinghas been completed, the gate assembly 48 is pivoted in a clockwisedirection from the position of FIG. 4 to the position of FIG. 5 by meansof a gate control rod 58 which is connected to the armature of a gatecontrol solenoid 60 (FIG. 1). The gate assembly 48 is normallymaintained ained in the stop position (FIG. 4) by means of acoil spring62 (FIG. 1) which tends to withdraw the armature from the solenoid coilof the gate control solenoid 60. When the solenoid is energized, thearmature is pulled in and the control rod 58 exerts a clockwise torqueon the gate assembly 48 against the bias of the spring 62 to move theassembly to the open position (FIG. 5). This opens the gate and permitsthe discharge of the original 26 when the belt 20 is moved.

The top one of the original documents 26 in the stack contained in thetray 36 is picked off by a feeder assembly conventional per se andgenerally indicatd as 64 (FIG. 1), and is advanced from left to right,as shown in FIG. 3 by the arrow B, toward an upwardly sloping rampmember 66. The leading edge portion of the document advanced by thefeeder assembly 64 moves up the sloped ramp 66 and is engaged between afirst pair of rollers 68'and 70, each having a sleeve of rubber or otherfrictional material on the outer surface thereof to provide goodfrictional contact with the document.

As the document moves between the rollers 68 and 70, it is turneddownwardly toward the main roller 24 by a plurality of laterally spacedapart, endless belts 72 which are trained around grooves provided in theupper roller 68 on the one hand and in grooves formed on a lower roller74 (FIG. 3). The belts 72 are circular in cross-section and arepreferably formed of flexible plastic material having suitablefrictional qualities for engaging the surface of the document 26. Aseach document 26 passes between the upper pair of rollers 68 and 70, theplurality of spaced apart belts 72 guide the leading edge of thedocument 26 downwardly past a V shaped deflector 76 to engage theendless belt 20 as it is trained around the roller 24. As the leadingedge of the document 26 passes around the roller 24, it is guided to theleft and under the roller 24 by the plurality of belts 72 and aplurality of transversely spaced guide fingers 78 having curved uppersurfaces thereon substantially conforming to the path of the undersideof.

the main endless belt 20 (FIG. 3). As shown in FIG. 2, the fingers 78are spaced between the belt loops 72 and direct the leading edge of thedocuments down towards the exposure platen l4 beneath the endless belt20.

A portion of the roller 24 is spaced upwardly above the upper run of theendless belt 20. In order to provide the desired tension on this belt,a-tension roll 80 is provided adjacent the right-hand end of the upperrun support member 42 and upwardlyand to the left of the roller 24. Therollers 68, 70, 74,"and 80 are provided with outer belt engaging sleevematerial which is resilient and has good frictional characteristics forcontact with the belt 20 or the document 26.

Each of the rollers is supported on a shaft extending between the frontand rear side plates 30 and 32. The main belt roller 24 is supported onan axle or a drive shaft 82 for controlled rotation in'a clockwisedirection (FIG. .3). Motive power rotating the main roller drive shaft82 is supplied by an electric motor-84 and gear reducing unit 86 (FIG.1). Three axles 88, 90, and 94 supporting the rollers 68, 70, and 74,respectively, are driven in synchronism with the roller 24 to provideproper direction and speed of drive for the belts 72 which move incounterclockwise direction contrasted with the clockwise movement of themain endless belt 20. The drive shafts 82, 88, 90, and 94 are drivinglyconnected by a link chain 92 or toothed belt to insure proper speed anddirection of rotationof the various shafts.

In operating the document feeder 10, the operator places a plurality oforiginal documents 26 in the feed tray 36 and then through the controlhead 33 manually enters information relating to the desired number ofcopies of each of the documents 26. The operator then initiates a startcycle by depressing a manual feed switch 111 causing the feeder assembly64 to feed the top document in the stack toward the right.(FIG. 3), upthe sloping ramp 66, and between the first pair of rollers 68 and 70.The document is then fed downwardly by the belts 72 around the roller 24intocontact with the endless belt 20. This belt moves the document 26into contact with and along the exposure platen 14 of the copy machine12 until the leading edge of the document strikes the right-hand edge ofthe stop member 54 of the gate assembly 48 which isthen in a stopposition (FIG. 4). When the document 26 reaches the copy position withthe end in engagement with the stop member 54, it is ready for copying.The copy machine 12 is activated to make the desired number of copies.

After the copies have been reproduced, the gate assembly 48 is opened(FIG. 5) by operation of the gate solenoid 60; and the belt 20 is againenergized-through the motor drive 84 to rotate the feed roller 24 in aclockwise direction. With the gate open, the document 26 is moved to theleft (FIG. 5), and discharged as indicated by the arrow A. At the sametime, the next document in the stack of documents on the tray 36 ismoved into position by the feeder assembly 64. The cycle is continueduntil the supply of original documents is exhausted.

Control Circuit A preferred embodiment of a circuit for controlling theoperation of the document feeder 10 is illustrated in FIG. 9. Thecontrol circuit 100 operates in conjunction and in synchronization withthe control circuit in the copy machine 12 shown (FIG. 5) and describedin the above-identified copending application Ser. No. 889,594. In theensuing description, reference is made to the circuit for the machine12, and reference numbers referring to this circuit are identified belowby a suffix character X. For example; a start button 80 for the copymachine 12 is identified herein as 80X.

1. Power On and Preset To begin operation, the on-off button 80X of thecopy machine disclosed in the aforementioned copending US. Pat.application Ser. No. 889,594 is depressed to place that machine inoperation. The document feeder is also activated by the on-off button ofthe copy machine and derives its logic and relay voltage from the biaspower pack 228X of the copy machine. In the following description of theoperation of the control circuit of the document feeder, referenceshould generally be made to FIG. 9 of the instant drawings and to FIG.of the drawings of the aforementioned copending application Ser. No.889,594.

After the copy machine is originally turned on, the preset timer 245X ofthe copy machine provides a positive pulse to set the control registersof the control circuit of the copy machine to an initial state. Thispreset pulse is also applied to a tenninal 103 of the feeder controlcircuit 100. The preset pulse is effective to set the control registersof the control circuit 100 to an initial off state. The present pulsesets a first jam check register 106 which includes a pair ofcross-coupled NOR gates K24 and K25, in an off state. The controlregister 106 is placed in an off state in the following manner. Thepositive preset pulse is applied to the input of an OR gate K23. Thisrenders the output of gate K23 positive, which output is applied to theinput of the NOR gate K25. This results in a negative output from thegate K25 and a positive output from the gate K24. The output from thegate K24 places a transistor 129 in a conductive condition to hold acapacitor 131 in a relatively discharged state, thereby maintaining anSCR 133 in a nonconductive state.

In a like manner, the positive preset pulse sets the second jam checkregister 110, including a pair of cross-coupled NOR gates K29 and K30; ajam detector register 108, including a pair of cross-coupled NOR gatesK27 and K28; a gate control register 102, including a pair ofcross-coupled NOR gates K12 and K13; a feeder control register 104,including a pair of crosscoupled NOR gates K5 and K6; and a motorcontrol register 112, including a pair of cross-coupled NOR gates K andK21, in an off state. The operation of these control registers isbasically the same as the operation of the first jam check register 106described above.

The trailing edge of the positive preset pulse is further detected by aNOR gate K8 resulting in a positive output therefrom to the input of apreset one-shot 130. The preset one-shot 130 includes an OR gate K9having its output coupled across a series capacitor to one of its inputleads and a parallel RC circuit connected between that input lead andground potential. When a positive voltage, greater than the thresholdvoltage of the gate K9 appears at the output of the gate K9, it isinstantaneously coupled across the series capacitor back to its input torapidly increase the rise time of the leading edge of the output pulsefrom the gate K9.

A positive voltage is subsequently continuously applied to the input ofthe gate K9 from the parallel RC circuit until the voltage across theparallel capacitor, in discharging through the parallel resistorconnected to ground potential, drops below the threshold level of thegate K9. At that time, the output of the OR gate drops from positivelogic voltage to ground potential. When this occurs, a diode connectedin parallel with the par allel RC circuit and having its anode connectedto ground potential becomes forward biased and rapidly discharges theseries capacitor connected between the output and the input of the gateK9. Since the pulse width of the positive output pulse from the gate K9depends upon the time constant of the parallel RC circuit, the pulsewidth may be easily set in advance to the value required.

The preset one-shot 130 provides a positive pulse to the inputs of ORgates K10 and K22 to temporarily turn on transistors 119 and 127,respectively. These transistors in their on condition energize the gatesolenoid 60 and the motor solenoid 118 to place the gate assembly 48 inan open position (FIG. 5) and turn on the main drive motor 84, both fora period of time determined by the pulse width of the positive pulsefrom the preset one-shot 130. At the end of the pulse from the presetone-shot 130, transistors 119 and 127 are turned off, therebydeenergizing both the gate solenoid 60 and the motor solenoid 118. Thegate assembly 48 thus assumes a stop position (FIG. 4), and the drivemotor 84 is turned off. This aforementioned temporary opening of thegate assembly 48 and energization of the drive motor 84 occur in orderto eject any original document that may have been left on the exposureplaten 14 of the copy machine 12 at the end of the last operation.

2. Document Feed Initiation The document feeder is now in a condition totransport original documents. The operator may now load the originaldocuments 26 (FIG. 1) into the receiving tray 36 of the document feeder.After loading the original documents, the operator programs the numberof copies of the original documents desired into the control head 33.This in turn sets an exposure counter 113 (FIG. 9) to the number ofcopies desired. The counter 1 13 counts the number of copies of eachoriginal document that has been made and is advanced in response to thepulses from an AND gate G21X of the copy machine 12.

The counter 113 provides a positive signal to NOR gate K16 (FIG. 9) whenit is set at or registers zero. This results in a negative output fromgate K16, turning off transistor 117 and placing a high voltage on alead line 115 vhich is connected to terminal 412X of the copy machine.When the counter 113 is set at or registers a number greater than zero,it provides a ground signal to the input of gate K16. This results in apositive voltage output therefrom turning on transistor 117 and placingterminal 412x of the copy machine 12 essentially at ground potential.Thus, transistor 117 operates as a multiple copy request switchcontrolling the outputs of the multiple copy enabling gates 61K and 62Kof the copy machine.

The output voltage of the exposure counter 113 further affects theoperation of the feeder assembly 64 (FIG. 1). When the output voltage ispositive, as occurs when the counter 1 13 (FIG. 9) registers zero, oneinput to NOR gate K7 thus also is positive. Transistor 126 and thefeeder assembly 64 controlled thereby are held in an off condition toprevent any feeding of original documents 26 into the document feeder10. When the output voltage of the exposure counter 113 is at groundpotential, as occurs when the counter 113 registers any number greaterthan zero, the inhibit, that is, the positive voltage, is removed fromthe input to NOR gate K7. Thus, transistor 126 and the feeder assembly64 are capable of being placed in an on condition when the voltage onthe other input of NOR gate K7 is also at ground potential.

To begin the copy process, the manual feed switch 1 11 (FIG. 9) isdepressed which sets the feeder control register 104 and the motorcontrol register 112 to on states to turn on transistors 126 and 127,respectively, which in turn energize a feeder solenoid 116 and the motorsolenoid 118. The energization of the feeder solenoid 1 16 operates thefeeder assembly 64 to begin the feeding of an original document 26 fromthe stack of original documents in the receiving tray 36 of the documentfeeder into the document transport path as illustrated by arrow B (FIG.3). The energization of the motor solenoid 118 controls the energizationof the drive motor 84 to rotate the rollers 24, 68, and 70.

When the leading edge of an original document defleets the feeder resetswitch 107, a positive pulse is provided through a gate K14 to an inputof the gate K6 to change the state of the feeder register 104, therebyturning off the transistor 126 through the gate K7 This results in thedeenergization of the feeder solenoid l 16, causing the feeder assembly64 to stop any further feeding of the original documents 26 along thedocument transport path.

Additionally, the feeder reset switch 107 provides a positive pulse to amotor one-shot 132, which in turn provides a positive pulse of apredetermined variable pulse width to the capacitor 128. Theconstruction and operation of the motor one-shot 132 is essentially thesame as that of the preset one-shot 130 discussed above, except for theuse of a variable resistor 124 in the parallel RC circuit. The pulsewidth of the positive pulse from the motor one-shot 132 may be varied byadjusting a wiper arm of the variable resistor 124.

A NOR gate K18 responds to the trailing edge of the positive pulse fromthe motor one-shot 132 to provide a positive output through a gate K19to reset the motor register 112 to an off condition, thereby turning offthe transistor 127. This results in the deenergization of the motorsolenoid 118 to thereby deenergize the motor 84. It should be noted,however, that the motor 84 remains on after the feeder reset switch 107is deflected for a period of time determined by the pulse width of thepositive pulse from the motor one-shot 132. The time that the motor 84is held on after the tripping of the feeder reset switch 107 isadjustedto permit the leading edge of the original document 26 to betransported along the document transport path to a position abutting theblocking edge of the gate assembly 48 (FIG. 4). The position of theleading edge of the original document 26 in relation to the gateassembly 48 may be altered by suitably adjusting the wiper arm of thevariable resistor 124 of the motor one-shot 132. In addition, to insureagainst buckling, the endless belt 20, as discussed above, is designedto slip or slide over the back surface of the original document 26 whenit is in contact with the gate assembly 48.

3. Copy Machine Initiation In response to the tripping of the feederreset switch 107, a positive pulse is provided to the copy machine 12from a terminal 109 of the document feeder 10 to the input of a gate G6Xof the copy machine to begin the feeding of the copy material into thecopy material transport path of the copy machine 12. The copy machine 12then proceeds to make the number of copies of the original document 26previously programmed into the exposure counter 113.

4. Document Feed Reinitiation When the exposure counter 113 counts downto zero during the copying process, advantageouslyin response to asignal from the output of AND gate G21X of the copy machine 12 generatedat the occurrence of a copy material cutting operation, a positivevoltage is applied to the inputs of NOR gates K7 and K16 from theexposure counter 113 to prevent the activation of the feeder assembly 64and to remove the copy machine 12 from the multiple copy mode. As soonas the last copy being processed of an original document 26 is detectedby the exposure sensor 192x of the copy machine, a signal is generatedby the exposure sensor 192X. The trailing edge of this signal may beused to reset the exposure counter 113 to the number of copies selectedby the machine operator at the start of the copying operation, to removethe inhibit preventing activation of the feeder assembly 64, and toreturn the copy machine 12 to the multiple copy mode.

The exposure counter 1 13 may be reset to zero when a feeder timer 134completes its time-out period or when power to the document feeder l0and to the copy machine 12 is terminated. Alternatively, the exposurecounter 113 may be left set at the number of copies selected for thelast copy operation and changed, if desired, at the time of the nextcopy operation.

When the exposure counter 113 reaches zero and removes the copy machine12 from the multiple copy mode, the xenon and corona control register300X of the copy machine 12 is thereby enabled to change states inresponse to the leading edge of the next signal from the exposure sensor192X of the copy machine 12. The next signal from the exposure sensor192x occurs when the last copy of the preselected number of copies isdetected.

Terminal 101 of the document feeder is connected to the output of gateXC2X of the xenon and corona control register 300x. When the xenon andthe corona control register 300x changes state after the exposure of thelast copy of an original document 26, the output from the gate XCZXswitches from ground potential to a positive voltage. This positivevoltage changes the state of the gate register 102 to energize the gatesolenoid 60, thereby moving the gate assembly 48 to an open position(FIG. 5). Simultaneously, the motor register 112 changes state tothereby energize the motor solenoid 118 and thereby turn on the motor84.

Simultaneously, the first jam check register 106 and the second jamcheck register 110 change state to turn off the transistors 129 and 139,respectively. This initiates the time-out period of each of the jamcheck circuits.

Turning on the motor 84 results in rotating the roller 24 and theendless belt 20. With the gate assembly 48 in an open position (FIG. 5)and the endless belt 20 rotating in a clockwise direction, the originaldocument 26 is normally expelled from the exposure platen 14.

At the exit of the document feeder 10 is an output sensor (FIG. 3). In apreferred embodiment, sensor 105 comprises a photoelectric cell thatprovides a positive output signal when its light beam is interrupted byan original document 26 that is being expelled from the document feeder10 and a ground output signal when its light beam is uninterrupted.Alternatively, a miniature mechanical switch may be used in the place ofthe photoelectric cell. When the leading edge of an original documentbeing expelled from the document feeder is detected by the sensor 105, apositive pulse is provided through OR gates K3 and K4 to the input ofNOR gate K5 to change the state of the feeder register 104, therebyturning on the transistor 126. When the transistor 126 turns on, thefeeder solenoid 116 is energized to reinitiate the operation of thefeeder assembly 64. This results in the second original document 26 fromthe stack of original documents being fed into and along the documenttransport path of the document feeder l0.

Simultaneously, with the changing of the state of the feeder register104, the sensor 105 provides a positive pulse through an OR gate K23 tochange the state of the first jam check register 106, to thereby turn onthe transistor 129. Assuming that this occurs before the time-out periodof the first jam check circuit has run, the time-out period is therebyinterrupted and the capacitor 131 is discharged through the transistor129, thereby maintaining the SCR 133 in a nonconductive state.

When the trailing edge of the original document 26 passes the sensor105, the pulse from the sensor 105 falls from a positive voltage togound potential. This change in voltage levels results in a negativepulse at the input of the NOR gate K11. The positive output from thegate K11 resulting therefrom is used to reset the gate register 102 andthe second jam check register 110 to deenergize the gate solenoid 60 andto interrupt the time-out period of the timing circuit of the second jamcheck circuit, respectively. Deenergizing the gate solenoid 60 causesthe gate assembly 48 to move to its stop position (FIG. 4).

5. Jam Check Operation During the time-out periods of the first andsecond jam check circuits, capacitors 131 and 141 are being chargeduntil the voltage developed across these capacitors is sufficient torender the SCRs 133 and 143 conductive. The first jam check circuitmonitors the transfer of the leading edge of the original document 26,and the second jam check circuit monitors the transfer of the trailingedge of the original document 26. Thus, the time-out periods of thesejam check circuits are different in that the time-out period of thefirst jam check circuit is shorter than the time-out period of thesecond jam check circuit. The time-out periods are determined by the RCtime constants of the respective jam check circuits.

If either the leading edge of the original document 26 jams and fails topass the sensor 105 before the timeout period of the first jam checkcircuit has run or the trailing edge of the original document 26 failsto pass the sensor 105 before the time-out period of the second jamcheck circuit has run, a positive signal will be applied from either oneor both of the jam check circuits to the input of gate K26. This in turnresults in a positive signal being applied to the input of the gate K27,thereby changing the state of the jam detector register 108. This changeof state results in the output of the gate K28 going positive, therebyturning on transistor 137 and lighting a jam lamp 120 which isphysically located on the control head 33 (FIG. 1).

A positive signal is also provided from the jam detecting circuitthrough the gate K19 to the input of the gate K20 to change the state ofthe motor register 112. This results in the turning off of thetransistor 127 and the deenergization of the motor solenoid 118 tothereby turn off the motor 84. A positive signal is additionallyprovided to the inputs of NOR gates K2 and K11 to prevent a subsequentsignal from the output sensor from changing the states of the controlregisters of the document feeder control circuit. The expiration of thetime-out period of a feeder timer 134 will subsequently deactivate thefeeder assembly 64, assuming that it had been activated in response tothe timely detection of the leading edge of an original document 26 bythe sensor 105.

Simultaneously with the lighting of the jam lamp 120, a positive signalis applied to the copy machine malfunction circuit. Terminal 135 isconnected to the input of a gate JD2X of a bistable jam detectingcircuit 332x of the copy machine 12. Applying a positive input to thegate JDZX changes the state of the bistable jam detecting circuit 332xand thus shuts down the copy machine 12. A jam lamp 96X and service lamp86X turn on; and a manual jam reset switch contact 98aX is closed byrelay K3X of the copy machine 12.

Since a transistor 307X in a corona control circuit of the copy machine12 is turned off under a jam condition, a remote trip timer 244x of thecopy machine begins to time-out. Approximately 25 seconds later, theremote trip timer 244X energizes a relay K2X of the copy machine 12.This in turn disconnects a contact K2aX resulting in the deenergizationof the copy machine 12.

After the jam in the document feeder 10 has been cleared, the documentfeeder 10 and the copy machine 12 will begin to operate again only aftera manual jam reset switch 98X of the copy machine 12 is pressed to openthe switch contact 98aX. Thus, a specific positive act is required ofthe operator before the document feeder l0 and the copy machine 12 canbe rendered operative again.

6. Power Off Assuming that the last original document 26 has been copiedand is being expelled from the document feeder 10, means are provided toturn the document feeder 10 and the copy machine 12 off. The feedertimer 134, comprising a transistor 121, a variable resistor 122, acapacitor 123, and an SCR accomplishes this object.

When the sensor 105 detects the leading edge of an original document 26being expelled from the document feeder 10, it provides a positive pulseto turn on the feeder assembly 64 and to simultaneously turn off thetransistor 121. The turning off of the transistor 121 initiates thetime-out period of the feeder timer 134. The feeder timer 134 operatesessentially the same as, but has a different time-out period than, thetiming circuits for the first and second jam check circuits previouslydiscussed.

The time-out period of the feeder timer 134 may be adjusted by varyingthe position of a wiper arm of the variable resistor 122. The time-outperiod of the feeder timer 134 may be interrupted when the next originaldocument 26 from the stack in the receiving tray 36 of the documentfeeder 10 deflects the feeder reset switch 107 after being fed into andalong the document transport path by the feeder assembly 64. If copiesof the last original document 26 have just been completed, the feederassembly 64 will not be able to feed another original document 26 intoand along the document transport path. Thus, the feeder reset switch 107will not be deflected and the time-out period of the feeder timer 134will run out.

When this occurs, the SCR 125 is rendered conductive and provides apositive output pulse to reset both the motor register 1 l2 and thefeeder register 104. This results in turning off transistor 127 and 126,respectively, thereby deenergizing the motor solenoid 118 and the feedersolenoid 116 to deactivate the motor 84 and the feeder assembly 64.

The time-out period of the remote trip timer 244X of the copy machine 12continues to run during the timeout period of the feeder timer 134 ofthe document feeder 10. After the copying of the last original document26 and the expiration of the time-out period of the feeder timer 134,the document feeder is deactivated. Thus, since no further copyingdemands are presented to the copy machine 12 from the document feeder10, the remote trip timer 244X of the copy machine times-out. Thisresults in activating relay K2X of the copy machine to open a contactK2aX of the copy machine 12, thereby deenergizing the copy machine 12and the document feeder 10.

Thus, a new and improved automated document feeder has been provided fortransferring original documents 26 one at a time in succession into acopying position on the exposure platen 14 of a copy machine 12.Obviously, many modifications and variations of the present inventionare possible in light of the above teachings. It is therefore to beunderstood that, within the scope of the appended claims, the inventionmay be practiced otherwise and as specifically described.

What is claimed and desired to be secured by Letters Patent of theUnited States is:

l. A device for controlling the operation of an assembly associated withcopy-making apparatus for transporting a document from an input stationalong a transport path past an exposure station to an exit station, saidassembly including drive means for transporting said document from saidinput station along said transport path to said exit station, gatingmeans positioned at said exposure station movable between an openposition and a blocking position and feeding means positioned at saidinput station for feeding said document into said transport path, saiddevice comprising means for initiating the operation of said assembly,

first sensing means disposed along said transport path for detecting thepresence of said document, second sensing means disposed at said exitstation for detecting the presence of said document, means operable atthe initiation of the operation of said assembly for moving said gatingmeans to an open position and for energizing said drive means both onlyfor a predetermined time period to remove a document from said exposurestation,

means for energizing the feeding means to feed a document into thetransport path both in response to a signal from said initiating meansand also in response to a signal from said second sensing means and fordeenergizing the feeding means in response to a signal from said firstsensing means,

means for moving said gating means to said blocking position both aftersaid predetermined time period and in response to said signal from saidsecond sensing means to provide a means for registering said document atsaid exposure station in position for exposure by said copy-makingapparatus,

means for moving said gating means to said open position subsequent tothe exposure of said document at said exposure station to enable saiddocument to be transported to said exit station,

means for energizing said drive means in response to a signal from saidinitiating means and also subsequent to the exposure of said document atsaid exposure station to transport said document along said transportpath and means for deenergizing said drive means in response to a signalfrom said first sensing means to interrupt the transporting of saiddocument at a position in abutment with said gating means at saidexposure station.

2. The device defined in claim 1 further comprising timing means havinga predetermined time-out period initiated both in response to a signalfrom said initiating means and inresponse to said signal from saidsecond sensing means for deactivating said transporting assembly at theexpiration of said time-out period, said time-out period being capableof being interrupted in response to a signal from said first sensingmeans to thereby prevent the deactivation of said transporting assembly.

3. The device defined in claim 1 further comprising plural jam checkmeans, each having a predetermined time-out period and each beingcapable of deactivating said transporting assembly at the expiration ofits respective time-out period,

the time-out period of a first one of said plural jam check means beingcapable of being interrupted in response to a first portion of saidsignal from said second sensing means to thereby prevent thedeactivation of said transporting assembly,

the time-out period of a second one of said plural jam check means beingcapable of being interrupted in response to a second portion of saidsignal from said second sensing means to thereby prevent thedeactivation of said transporting assembly.

1. A device for controlling the operation of an assembly associated withcopy-making apparatus for transporting a document from an input stationalong a transport path past an exposure station to an exit station, saidassembly including drive means for transporting said document from saidinput station along said transport path to said exit station, gatingmeans positioned at said exposure station movable between an openposition and a blocking position and feeding means positioned at saidinput station for feeding said document into said transport path, saiddevice comprising means for initiating the operation of said assembly,first sensing means disposed along said transport path for detecting thepresence of said document, second sensing means disposed at said exitstation for detecting the presence of said document, means operable atthe initiation of the operation of said assembly for moving said gatingmeans to an open position and for energizing said drive means both onlyfor a predetermined time period to remove a document from said exposurestation, means for energizing the feeding means to feed a document intothe transport path both in response to a signal from said initiatingmeans and also in response to a signal from said second sensing meansand for deenergizing the feeding means in response to a signal from saidfirst sensing means, means for moving said gating means to said blockingposition both after said predetermined time period and in response tosaid signal from said second sensing means to provide a means forregistering said document at said exposure station in position forexposure by said copy-making apparatus, means for moving said gatingmeans to said open position subsequent to the exposure of said documentat said exposure station to enable said document to be transported tosaid exit station, means for energizing said drive means in response toa signal from said initiating means and also subsequent to the exposureof said document at said exposure station to transport said documentalong said transport path and means for deenergizing said drive means inresponse to a signal from said first sensing means to interrupt thetransporting of said document at a position in abutment with said gatingmeans at said exposure station.
 2. The device defined in claim 1 furthercomprising timing means having a predetermined time-out period initiatedboth in response to a signal from said initiating means and in responseto said signal from said second sensing means for deactivating saidtransporting assembly at the expiration of said time-out period, saidtime-out period being capable of being interrupted in response to asignal from said first sensing means to thereby prevent the deactivationof said transporting assembly.
 3. The device defined in claim 1 furthercomprising plural jam check means, each having a predetermined time-outperiod and each being capable of deactivating said transporting assemblyat the expiration of its respective time-out period, the time-out periodof a first one of said plural jam check means being capable of beinginterrupted in response to a first portion of said signal from saidsecond sensing means to thereby prevent the deactivation of saidtransporting assembly, the time-out period of a second one of saidplural jam check means being capable of being interrupted in response toa second portion of said signal from said second sensing means tothereby prevent the deactivation of said transporting assembly.